This is a request for the continuation of an ADAMHA RSDA Level II. During the seventeen years since receiving my Ph.D., my research has focused on the identification of pathways through which environmental and psychosocial stressors, and social supports influence behavior, psychological distress and physical health. I was trained as a social psychologist and the research and theoretical agendas I pursued during most of this period reflect that perspective. With support of the RSDA, I have spent the last four years broadening that perspective by learning about and conducting research on the role of biological pathways in linking stress and social influences of stress and support on the etiology of infectious disease. My current work addresses influences of stress and support on the etiology of infectious disease. The goal of this work is to develop and test sophisticated psycho-biologic models of the etiologic role of psychosocial factors in disease pathogenesis. In regard to growth, my overall goal is to improve my ability to understand and study biologic pathways through which psychosocial factors may influence susceptibility to infectious disease. Specific goals include the acquisition of basic background in virology, infectious diseases, neuroendocrine systems, some specific areas of immunology including processes involved in inflammation and symptom mediation, and primate behavior. My plans include formal classes, extensive reading in the targeted areas, collaborations, consultations, discussions with leading experts, and visits to other research facilities. The empirical work consists of three separate but interrelated projects addressing the roles of stress and social support systems in immunity and susceptibility to infectious disease. The projects include prospective research in which we measure psychologic and immunologic states and then challenge human volunteers with upper respiratory viruses; experimental research in which nonhuman primates are randomly assigned to stressful or nonstressful conditions and then challenged with upper respiratory viruses; and experimental research in which humans are exposed to acute laboratory stressors and their cellular immune response assessed. The primary aims of this program of research include establishing the effects of stressors on susceptibility to upper respiratory infection, examining behavioral, neuroendocrine and immune mediators of this relation, and investigating stable individual differences that might influence stressor elicited disease susceptibility.